If a bond is taxable it is usually noted in the title of the issuance, front cover, or the tax section of the official statement.
Under present federal income tax law, the interest you receive from investing in municipal bonds is free from federal income taxes. In most states, interest received from securities issued by governmental units within the state is also exempt from state and local taxes. However, the federal government may not permit the tax-exempt status to deals that don’t provide a major benefit to the public.
Consult your accountant and the Official Statement for details.